RECEIVING DEVICE, SEMICONDUCTOR INTEGRATED CIRCUIT, TRANSMITTING/RECEIVING DEVICE, TRANSPORT APPARATUS, PORTABLE TRANSMITTING/RECEIVING DEVICE, COMMUNICATION SYSTEM AND RECEIVING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a receiving device reducing current consumption during no communication without decelerating a response speed to a signal from a base station.

SOLUTION: A receiving device includes a receiver circuit 1 for outputting a received signal as a reception electric field intensity signal to a comparator circuit 3, an operation control circuit 4 for controlling an operation of the receiver circuit 1, and an intermittent reception control circuit 5 for outputting a periodic signal. The comparator circuit 3 holds a first threshold indicating that the receiving device has entered a communication area and a second threshold indicating a start of a continuous electric field intensity measurement. If the reception electric field intensity signal is lower than the second threshold, the operation control circuit 4 makes the receiver circuit 1 perform intermittent operation so that power consumption in the receiver circuit 1 can be reduced outside the communication area. If the reception electric field intensity signal is equal to or higher than the second threshold, the operation control circuit makes the receiver circuit 1 perform a continuous operation, and if the reception electric field intensity signal is equal to or higher than the first threshold, the operation control circuit makes a demodulation circuit 2 perform an operation, so that communication is performed without delay within the communication area.

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